Vulnerability-Lookup

CNVD-2021-44914

Vulnerability from cnvd - Published: 2021-06-24

Title

D-Link DIR-2640-US不正确访问控制漏洞

Description

D-Link DIR-2640-US是一款网络路由器设备。 D-Link DIR-2640-US存在安全漏洞，攻击者可利用漏洞使用telnet登录、修改路由信息、监视路由器下所有设备的流量、劫持DNS和网络钓鱼攻击。

Severity

中

Patch Name

D-Link DIR-2640-US不正确访问控制漏洞的补丁

Patch Description

D-Link DIR-2640-US是一款网络路由器设备。 D-Link DIR-2640-US存在安全漏洞，攻击者可利用漏洞使用telnet登录、修改路由信息、监视路由器下所有设备的流量、劫持DNS和网络钓鱼攻击。目前，供应商发布了安全公告及相关补丁信息，修复了此漏洞。

Formal description

用户可参考如下厂商提供的安全补丁以修复该漏洞： https://www.dlink.com/en/security-bulletin/

Reference

https://nvd.nist.gov/vuln/detail/CVE-2021-34203

Impacted products

Name
D-Link DIR-2640-US 1.01B04

Show details on source website

JSON

To clipboard

{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2021-34203"
    }
  },
  "description": "D-Link DIR-2640-US\u662f\u4e00\u6b3e\u7f51\u7edc\u8def\u7531\u5668\u8bbe\u5907\u3002\n\nD-Link DIR-2640-US\u5b58\u5728\u5b89\u5168\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u5229\u7528\u6f0f\u6d1e\u4f7f\u7528telnet\u767b\u5f55\u3001\u4fee\u6539\u8def\u7531\u4fe1\u606f\u3001\u76d1\u89c6\u8def\u7531\u5668\u4e0b\u6240\u6709\u8bbe\u5907\u7684\u6d41\u91cf\u3001\u52ab\u6301DNS\u548c\u7f51\u7edc\u9493\u9c7c\u653b\u51fb\u3002",
  "formalWay": "\u7528\u6237\u53ef\u53c2\u8003\u5982\u4e0b\u5382\u5546\u63d0\u4f9b\u7684\u5b89\u5168\u8865\u4e01\u4ee5\u4fee\u590d\u8be5\u6f0f\u6d1e\uff1a\r\nhttps://www.dlink.com/en/security-bulletin/",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2021-44914",
  "openTime": "2021-06-24",
  "patchDescription": "D-Link DIR-2640-US\u662f\u4e00\u6b3e\u7f51\u7edc\u8def\u7531\u5668\u8bbe\u5907\u3002\r\n\r\nD-Link DIR-2640-US\u5b58\u5728\u5b89\u5168\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u5229\u7528\u6f0f\u6d1e\u4f7f\u7528telnet\u767b\u5f55\u3001\u4fee\u6539\u8def\u7531\u4fe1\u606f\u3001\u76d1\u89c6\u8def\u7531\u5668\u4e0b\u6240\u6709\u8bbe\u5907\u7684\u6d41\u91cf\u3001\u52ab\u6301DNS\u548c\u7f51\u7edc\u9493\u9c7c\u653b\u51fb\u3002\u76ee\u524d\uff0c\u4f9b\u5e94\u5546\u53d1\u5e03\u4e86\u5b89\u5168\u516c\u544a\u53ca\u76f8\u5173\u8865\u4e01\u4fe1\u606f\uff0c\u4fee\u590d\u4e86\u6b64\u6f0f\u6d1e\u3002",
  "patchName": "D-Link DIR-2640-US\u4e0d\u6b63\u786e\u8bbf\u95ee\u63a7\u5236\u6f0f\u6d1e\u7684\u8865\u4e01",
  "products": {
    "product": "D-Link DIR-2640-US 1.01B04"
  },
  "referenceLink": "https://nvd.nist.gov/vuln/detail/CVE-2021-34203",
  "serverity": "\u4e2d",
  "submitTime": "2021-06-18",
  "title": "D-Link DIR-2640-US\u4e0d\u6b63\u786e\u8bbf\u95ee\u63a7\u5236\u6f0f\u6d1e"
}

CVE-2021-34203 (GCVE-0-2021-34203)

Vulnerability from cvelistv5 – Published: 2021-06-16 19:02 – Updated: 2026-07-09 00:13

Summary

D-Link DIR-2640-US 1.01B04 is vulnerable to Incorrect Access Control. Router ac2600 (dir-2640-us), when setting PPPoE, will start quagga process in the way of whole network monitoring, and this function uses the original default password and port. An attacker can easily use telnet to log in, modify routing information, monitor the traffic of all devices under the router, hijack DNS and phishing attacks. In addition, this interface is likely to be questioned by customers as a backdoor, because the interface should not be exposed.

Severity

No CVSS data available.

CWE

Assigner

mitre mitre root

References

2 references

URL	Tags
https://www.dlink.com/en/security-bulletin/
https://github.com/liyansong2018/CVE/tree/main/20…

Show details on NVD website

JSON

To clipboard

{
  "containers": {
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      {
        "providerMetadata": {
          "dateUpdated": "2026-07-09T00:13:56.133Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
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              "x_transferred"
            ],
            "url": "https://www.dlink.com/en/security-bulletin/"
          },
          {
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              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/liyansong2018/CVE/tree/main/2021/CVE-2021-34203"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
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          "versions": [
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      ],
      "descriptions": [
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        }
      ],
      "problemTypes": [
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      "providerMetadata": {
        "dateUpdated": "2026-07-05T15:48:49.472Z",
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        "shortName": "mitre"
      },
      "references": [
        {
          "url": "https://www.dlink.com/en/security-bulletin/"
        },
        {
          "url": "https://github.com/liyansong2018/CVE/tree/main/2021/CVE-2021-34203"
        }
      ],
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "cve@mitre.org",
          "ID": "CVE-2021-34203",
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        },
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          "vendor": {
            "vendor_data": [
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                "product": {
                  "product_data": [
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                      "version": {
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                          {
                            "version_value": "n/a"
                          }
                        ]
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            ]
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        },
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        "data_version": "4.0",
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              "value": "D-Link DIR-2640-US 1.01B04 is vulnerable to Incorrect Access Control. Router ac2600 (dir-2640-us), when setting PPPoE, will start quagga process in the way of whole network monitoring, and this function uses the original default password and port. An attacker can easily use telnet to log in, modify routing information, monitor the traffic of all devices under the router, hijack DNS and phishing attacks. In addition, this interface is likely to be questioned by customers as a backdoor, because the interface should not be exposed."
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              "url": "https://www.dlink.com/en/security-bulletin/"
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            {
              "name": "http://dir-2640-us.com",
              "refsource": "MISC",
              "url": "http://dir-2640-us.com"
            },
            {
              "name": "https://github.com/liyansong2018/CVE/tree/main/2021/CVE-2021-34203",
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            }
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  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
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    "dateReserved": "2021-06-07T00:00:00.000Z",
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    "state": "PUBLISHED"
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.